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        <p>Library Version 11.2.5.3</p>
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            <h2 class="title" style="clear: both"><a id="repset_request"></a>DB_ENV-&gt;rep_set_request()</h2>
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      <pre class="programlisting">#include &lt;db.h&gt;

int
DB_ENV-&gt;rep_set_request(DB_ENV *env, u_int32_t min, u_int32_t max);  </pre>
      <p>
         The <code class="methodname">DB_ENV-&gt;rep_set_request()</code> method sets a
         threshold for the minimum and maximum time that a client waits
         before requesting retransmission of a missing message.
         Specifically, if the client detects a gap in the sequence of
         incoming log records or database pages, Berkeley DB will wait for
         at least <span class="bold"><strong>min</strong></span> microseconds before
         requesting retransmission of the missing record.  Berkeley DB will
         double that amount before requesting the same missing record
         again, and so on, up to a maximum threshold of 
         <span class="bold"><strong>max</strong></span> microseconds.
    </p>
      <p>
         These values are thresholds only. Replication Manager applications
         use these values to determine when to automatically request
         retransmission of missing messages. For Base API applications,
         Berkeley DB has no thread available in the library as a timer, so
         the threshold is only checked when a thread enters the Berkeley DB
         library to process an incoming replication message. Any amount of
         time may have passed since the last message arrived and Berkeley
         DB only checks whether the amount of time since a request was made
         is beyond the threshold value or not.
    </p>
      <p>
         By default the minimum is 40000 and the maximum is 1280000 (1.28
         seconds). These defaults are fairly arbitrary and the application
         likely needs to adjust these.  The values should be based on
         expected load and performance characteristics of the master and
         client host platforms and transport infrastructure as well as
         round-trip message time.
    </p>
      <p>
         The database environment's replication subsystem may also be
         configured using the environment's <a href="../../programmer_reference/env_db_config.html#env_db_config.DB_CONFIG" class="olink">DB_CONFIG</a> file.  The syntax
         of the entry in that file is a single line with the string
         "rep_set_request", one or more whitespace characters, and the
         request times specified in two parts: the min and the max.  For
         example, "rep_set_request 40000 1280000". Because the <a href="../../programmer_reference/env_db_config.html#env_db_config.DB_CONFIG" class="olink">DB_CONFIG</a>
         file is read when the database environment is opened, it will
         silently overrule configuration done before that time.
    </p>
      <p>
         The <code class="methodname">DB_ENV-&gt;rep_set_request()</code> method
         configures a database environment, not only operations performed
         using the specified <a class="link" href="env.html" title="Chapter 5.  The DB_ENV Handle">DB_ENV</a>
         handle.
    </p>
      <p>
         The <code class="methodname">DB_ENV-&gt;rep_set_request()</code> method may be
         called at any time during the life of the application.
    </p>
      <p>
         The <code class="methodname">DB_ENV-&gt;rep_set_request()</code> <span>
            <span>
                  method returns a non-zero error value on failure and 0 on success.
            </span>
            
        </span>
    </p>
      <div class="sect2" lang="en" xml:lang="en">
        <div class="titlepage">
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            <div>
              <h3 class="title"><a id="idp54175512"></a>Parameters</h3>
            </div>
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        <div class="sect3" lang="en" xml:lang="en">
          <div class="titlepage">
            <div>
              <div>
                <h4 class="title"><a id="idp54175312"></a>min</h4>
              </div>
            </div>
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          <p>
                  The minimum number of microseconds a client waits before requesting
                  retransmission.
             </p>
        </div>
        <div class="sect3" lang="en" xml:lang="en">
          <div class="titlepage">
            <div>
              <div>
                <h4 class="title"><a id="idp54186232"></a>max</h4>
              </div>
            </div>
          </div>
          <p>
                  The maximum number of microseconds a client waits before requesting
                  retransmission.
             </p>
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      <div class="sect2" lang="en" xml:lang="en">
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            <div>
              <h3 class="title"><a id="idp54176592"></a>Errors</h3>
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        <p>
             The <code class="methodname">DB_ENV-&gt;rep_set_request()</code> <span>
            <span>
                 method may fail and return one of the following non-zero errors:
            </span>
            
        </span>
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        <div class="sect3" lang="en" xml:lang="en">
          <div class="titlepage">
            <div>
              <div>
                <h4 class="title"><a id="idp54166912"></a>EINVAL</h4>
              </div>
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          <p>
                An invalid flag value or parameter was specified.
            </p>
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      <div class="sect2" lang="en" xml:lang="en">
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          <div>
            <div>
              <h3 class="title"><a id="idp54164624"></a>Class</h3>
            </div>
          </div>
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        <p>
            <a class="link" href="env.html" title="Chapter 5.  The DB_ENV Handle">DB_ENV</a>  
        </p>
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      <div class="sect2" lang="en" xml:lang="en">
        <div class="titlepage">
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            <div>
              <h3 class="title"><a id="idp54146632"></a>See Also</h3>
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          </div>
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        <p>
             <a class="xref" href="rep.html#replist" title="Replication and Related Methods">Replication and Related Methods</a> 
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